*{
    margin: 0;
    padding: 0;
}
.zong{
    width: 880px;
    height: 750px;
}
.header{
    width: 100%;
    height: 5.5%;
    
}
.main{
    width: 100%;
    height: 94.5%;
}
li{
    float: left;
    list-style: none;
    width: 80px;
    height: 40px;
    background-color:	WhiteSmoke;
    margin-right: 10px;
    line-height: 40px;
    
}
a{
    text-decoration: none;
    color: black;
    display: block;
    text-align: center;
}
a:hover{
    background-color: cornflowerblue;
}